Parking Minimums Create Too Many Parking Spots

The problems with parking minimums are both numerous and obvious. First and foremost, the convenience of off-street parking spaces promotes driving, even in cities with efficient and expansive transit systems. The more spaces developers must build, the less space they have for actual residential units, which raises rents; meanwhile, mandatory parking spaces can displace ground-level retailers. And last, if you're not into the whole sustainability or economics thing, off-street parking facilities just aren't very attractive.

Still it's often assumed that without parking minimum regulations in place developers would still build a great deal of parking spaces - perhaps even more than is required of them - to meet demand. But that might not be the case, according to a new report by the N.Y.U. Furman Center [PDF]. After a thorough review of minimum parking regulations and off-street spaces in New York City, the study authors concluded that "more parking spaces exist today than would have been built without the requirements":

Overall, the data suggest that parking requirements cause developers to build more parking spaces than they otherwise would based on what they believe their prospective tenants or buyers demand.

Minimum parking regulations vary across New York City. In some low-density neighborhoods, a new housing unit may require a single new parking space; in high-density ones, every 100 units may call for anywhere between 40 and 85 spots. (Many buildings are also eligible to waive the minimum.) The original, well-intentioned idea behind the minimums was to prevent developers from increasing competition for neighborhood on-street parking, which can cause traffic congestion and harm air quality.

On average, for every 100 new housing units built in the city, 43 off-street spaces are created, according to the new report. Most of these spaces are built in the four outer boroughs; Queens and Staten Island, for example, require effective minimums of 66 and 122 spots per 100 units, respectively. (In Manhattan, on the other hand, parking maximums in the core keep the number of free off-street spaces very low: 5 spaces per 100 units.)

The Furman Center report points out a number of inconsistencies with the minimum regulations that lead to the creation of more spaces than necessary. In a city with a transit system as accessible as New York's, for instance, the need for off-street parking should decrease at developments near subway or commuter rail stations. For the most part that seems to be the case: on average, developers must build 72 spots for 100 units in buildings beyond a half mile from a transit station, and only 29 spaces for those inside that distance.

But wasteful outliers do exist. Take, for instance, the 157 Myrtle Avenue building in downtown Brooklyn. Since the building has 631 units, the minimum parking regulation called for 252 parking off-street parking spaces, according to the Furman Center report, despite the fact that at least 10 subway lines are within walking distance. As a result, only half the building's spaces were leased as of last October.

More evidence that parking minimums lead to overbuilding comes from an examination of how many spaces developers actually construct. Of about 300 housing developments built in the last decade or so, 77 percent created the exact minimum number of parking spaces, or very near it. Small buildings, in particular, averaged right at the mandate: those with 5 to 9 units build exactly the required 5 spaces, and those with 10 to 14 units, exactly the required 7 spaces. These building patterns "suggest that developers would build fewer parking spaces without the requirements":

In addition to pointing out some important problems with New York's minimum parking mandate, the report offers a few potential solutions. The most obvious, of course, would be to reduce or eliminate the parking minimum, but a more palatable change might be to adjust them more precisely by neighborhood. If a building will be well-served by transit, then it shouldn't require as many spaces - a guideline followed by cities like Portland. Last, to mitigate any impact new buildings might have on street spaces, developers could pay a fee into a community transit fund that goes toward improving public transportation.